package com.itheima.variable;

public class Demo4Conversion {
    public static void main(String[] args) {
        byte d = 3 + 4;
        System.out.println(d);
        //这里的3,4是两个常量,java存在常量优化机制会在编译时就会让3和4相加,然后判断是否在范围
        //对于变量不行
        long num = 1232342342342342343l;
    }
}
